/* “ * ”代表所有*/
/* douban 国内最强前端团队 所有的css都需要reset，因为不同的浏览器内核执行逻辑会有偏差 */
/*性能不好*/
/* * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
} */
/* body, div, dl, dt, dd, ul, li, h1, h2, h3, h4, h5, h6, 
pre, code, form, fieldset, legend, input, button, textarea, blockquote {
    margin: 0;
    padding: 0;
}

html {
    font-size: 100px;
    height: 100%;
    width: 100%;
    overflow: hidden;
} */
/* CSS Reset */
html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, 
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
    margin: 0;
    padding: 0;
    border: 0;
    font-size: 100%;
    font: inherit;
    vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
    display: block;
}
body {
    line-height: 1;
}
ol, ul {
    list-style: none;
}
blockquote, q {
    quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
    content: '';
    content: none;
}
table {
    border-collapse: collapse;
    border-spacing: 0;
}

/*业务样式*/
html {
    height: 100vh;
    font-size: 10px;
    background: url(./background.jpg) bottom center;
    background-size: cover;
}
body,html {
    font-family: sans-serif;
}
.keys {
    /* 水平垂直居中 */
    display: flex;
    /* flex: 1; */
    align-items: center;/*主轴居中*/
    justify-content: center;/*水平居中*/

    min-height: 100vh;
}
.key {
    /* rem是最好的适配单位，因为它是相对于根元素的font-size的单位 */
    /* 适配 PC iPad Phone */
    /* 因为html中font-size 为10px，所以此处1rem = 10px; */
    /*蓝湖 设置 10px 为 font-size 方便换算*/
    border: .4rem solid #000;
    border-radius: .5rem;
    margin: 1rem;
    font-size: 1.5rem;
    padding: 1rem .5rem;
    /*all 只要这个元素的任何一个样式改变了，运用这个过渡动画*/
    transition: all .07s ease;    /* animation的简版，过渡动画 */
    width: 10rem;
    text-align: center;
    color: white;
    text-shadow: 0 0 .5rem black;
}

.playing {
    transform: scale(1.1);/*translate rotata scale*/
    border-color: rgb(236, 255, 127);
    box-shadow: 0 0 1rem rgb(217, 255, 127);
}

.key div {
    font-size: 4rem;

}

.sound {
    font-size: 1.2rem;
    text-transform: uppercase;
    letter-spacing: normal;
    color: #ffc600;
}